Polybrominated Diphenyl Ethers, Polybrominated Biphenyls, and Risk of Papillary Thyroid Cancer: A Nested Case-Control Study

Am J Epidemiol. 2020 Feb 28;189(2):120-132. doi: 10.1093/aje/kwz229.


A nested case-control study was carried out using data from the US Department of Defense cohort between 2000 and 2013 to investigate the associations of papillary thyroid cancer (PTC) with serum concentrations of polybrominated diphenyl ethers and polybrominated biphenyls. This study included 742 histologically confirmed PTC cases (in 341 women and 401 men) and 742 matched controls with prediagnostic serum samples from the Department of Defense Serum Repository. Lipid-corrected serum concentrations of 8 congeners were measured. Multivariate conditional logistic regression analyses were performed for classical PTC and follicular variant of PTC, respectively. We also examined effect modification by sex. BDE-28, a polybrominated diphenyl ether congener, was associated with significantly increased risk of classical PTC (for the third tertile vs. below the limit of detection, odds ratio = 2.09, 95% confidence interval: 1.05, 4.15; P for trend = 0.02), adjusting for other congeners, body mass index, and branch of military service. This association was observed mainly for larger classical PTC (tumor size > 10 mm), with a significantly stronger association among women than men (P for interaction = 0.004). No consistent associations were observed for other congeners, including those at higher concentrations. This study found a significantly increased risk of classical PTC associated with increasing levels of BDE-28. The risk varied by sex and tumor size.

Keywords: PBBs; PBDEs; papillary thyroid cancer; polybrominated biphenyls; polybrominated diphenyl ethers.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Case-Control Studies
  • Environmental Pollutants / blood*
  • Environmental Pollutants / toxicity
  • Female
  • Halogenated Diphenyl Ethers / blood*
  • Halogenated Diphenyl Ethers / toxicity
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Polybrominated Biphenyls / blood*
  • Polybrominated Biphenyls / toxicity
  • Thyroid Cancer, Papillary / chemically induced*
  • Thyroid Neoplasms / chemically induced*
  • Young Adult


  • Environmental Pollutants
  • Halogenated Diphenyl Ethers
  • Polybrominated Biphenyls
  • tribromodiphenyl ether 28